Well that sucks. :<
Your SDD probably had Winddows on it and thus the bootsectors. Without them the bootmanager doesnt know what to do (with your HDD). Installing Windows on it should fix the HDD WOULD BE MY GUESS.
SSD looks borked to me.
Yep, pretty sure the SSD is bricked. There's an issue with OCZ SSD's that means they don't like being put into sleep mode - would've been nice to know about that a few months ago
I got Windows installed on the HDD but then... well, read below.
What happeneds when you use "press blah to select boot device" and then select the USB key?
With memtest I got 'Disk I/O Error'. But yesterday I tried using the OCZ SSD firmware updater (the only known way to un-brick the SSD), which is basically a Linux environment that boots from a USB stick, and it booted just fine (although it couldn't detect the SSD either, so there's no way to fix it afaik).
edit: ah, I read your question slightly wrong. I don't think I've ever had a USB in and got that message, it's either Disk I/O error or a succesful boot with the OCZ tool.
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So after working out that my SSD was broken I managed to get Windows installed on my old HDD. Updated a bunch of drivers, did multiple reboots, no problems - it was looking good. But then I put my graphics card back in and I go straight back to the 'BOOTMGR is missing' error. At the moment I can reach BIOS, which only detects my DVD drive: HDD isn't being detected at all. I tried loads of times to boot from the Windows DVD, but it sounds like it isn't spinning properly in the DVD drive. Kept trying this whilst removing more and more hardware from the machine - nothing, even with the only the CPU, memory, PSU and DVD drive connected to the mobo. That's where I gave up last night.
Maybe it's a PSU issue if hooking up the graphics card fucked it? Maybe the Bootmgr problem was never really fixed and I just got lucky with the Windows install? I dunno what to think of it
I've still got my old mobo + cpu + memory, I guess I could test everything on that and see what happens. Although if anyone's got any other ideas I'd rather try them first before taking all the new shit out of my case and putting back in the old shit.